With a loose ferrule I wouldn't fish it. You should be able to replace the ferrule your self and it shouldn't cost a bundle either. See if you can get int touch with Russ and Erica Gooding here at Golden Witch:
http://www.goldenwitch.com/index.html
They specialize in getting the right ferrules for vintage boo without charging an arm and a leg. Shoot them an email. Even if you don't want to tackle the job yourself there are others on this board that build rods who may be able to help you. Replacing ferrules is pretty staight forward but it must be done correctly.
In order to get that old ferrule to tighten up, if indeed it will, you have to take it off of the rod, clean up the ferrule station so you might as well just install new ferrules. Just MHO.
Good luck.